Layers of Learning is a four year rotation program you can use with all of your children at once, 1st through 12th. It was written by homeschool moms for homeschoolers. It’s organized and packed with information, crafts, printables, games, web links, and book lists.Layers of Learning includes the subjects of history, geography, science, and the arts. Once you complete all four years you start over with the program and work through the units again, with an older, more capable student. So it’s cost effective too. Buy one program for four subjects for all of your kids clear through graduation.